Experimental investigation of the behavior of aramid fiber reinforced polymer confined concrete subjected to high strain-rate compression

• A series of quasi-static and SHPB tests were conducted on AFRP-confined concrete.
• AFRP-confined concrete outperformed unconfined concrete significantly under impact.
• An abnormal increase of dynamic strength was found in AFRP-confined concrete.
• Influence of strain rate effect was quantized by empirical formulae.
• The enhancement mechanism of AFRP during dynamic tests was illustrated.

This study investigated the behavior of aramid fiber reinforced polymer (AFRP) confined concrete subjected to high strain-rate compression. A total of 71 specimens were tested under quasi-static and high strain-rate axial compression using a hydraulically-driven testing system and a 100-mm-diameter split Hopkinson pressure bar apparatus, respectively. Influence of the loading rate was examined with strain rates ranging from 80 to 170 s−1. The influence of lateral confinement level was also examined by varying the number of AFRP layers and imposing different strain rates. The experimental results indicate that the dynamic strength, ultimate strain and energy absorption density are sensitive to strain rate, and that the external AFRP confinement significantly improves these properties. In addition, this paper discusses the strengthening and toughening mechanisms of AFRP jackets.